2024-03-04 11:31:44

by Viresh Kumar

Subject: [PATCH V2 1/2] OPP: debugfs: Fix warning with W=1 builds

We currently get the following warning:

debugfs.c:105:54: error: '%d' directive output may be truncated writing between 1 and 11 bytes into a region of size 8 [-Werror=format-truncation=]
snprintf(name, sizeof(name), "supply-%d", i);
^~
debugfs.c:105:46: note: directive argument in the range [-2147483644, 2147483646]
snprintf(name, sizeof(name), "supply-%d", i);
^~~~~~~~~~~
debugfs.c:105:17: note: 'snprintf' output between 9 and 19 bytes into a destination of size 15
snprintf(name, sizeof(name), "supply-%d", i);

Fix this and another potential issues it by allocating larger arrays.
Use the exact string format to allocate the arrays without getting into
these issues again.

Reported-by: kernel test robot <[email protected]>
Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
Signed-off-by: Viresh Kumar <[email protected]>
---
V2: Use string name while allocating memory for the array to fix potential
issues later on.

drivers/opp/debugfs.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/opp/debugfs.c b/drivers/opp/debugfs.c
index ec030b19164a..27c3748347af 100644
--- a/drivers/opp/debugfs.c
+++ b/drivers/opp/debugfs.c
@@ -56,11 +56,11 @@ static void opp_debug_create_bw(struct dev_pm_opp *opp,
struct dentry *pdentry)
{
struct dentry *d;
- char name[20];
+ char name[] = "icc-path-XXXXXXXXXX"; /* Integers can take 10 chars max */
int i;

for (i = 0; i < opp_table->path_count; i++) {
- snprintf(name, sizeof(name), "icc-path-%.1d", i);
+ snprintf(name, sizeof(name), "icc-path-%d", i);

/* Create per-path directory */
d = debugfs_create_dir(name, pdentry);
@@ -78,7 +78,7 @@ static void opp_debug_create_clks(struct dev_pm_opp *opp,
struct opp_table *opp_table,
struct dentry *pdentry)
{
- char name[12];
+ char name[] = "rate_hz_XXXXXXXXXX"; /* Integers can take 10 chars max */
int i;

if (opp_table->clk_count == 1) {
@@ -100,7 +100,7 @@ static void opp_debug_create_supplies(struct dev_pm_opp *opp,
int i;

for (i = 0; i < opp_table->regulator_count; i++) {
- char name[15];
+ char name[] = "supply-XXXXXXXXXX"; /* Integers can take 10 chars max */

snprintf(name, sizeof(name), "supply-%d", i);

--
2.31.1.272.g89b43f80a514

2024-03-04 11:32:08

by Viresh Kumar

Subject: [PATCH 2/2] OPP: debugfs: Fix warning around icc_get_name()

If the kernel isn't built with interconnect support, icc_get_name()
returns NULL and we get following warning:

drivers/opp/debugfs.c: In function 'bw_name_read':
drivers/opp/debugfs.c:43:42: error: '%.62s' directive argument is null [-Werror=format-overflow=]
i = scnprintf(buf, sizeof(buf), "%.62s\n", icc_get_name(path));

Fix it.

Reported-by: kernel test robot <[email protected]>
Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
Signed-off-by: Viresh Kumar <[email protected]>
---
drivers/opp/debugfs.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/opp/debugfs.c b/drivers/opp/debugfs.c
index 27c3748347af..a9ebfdf0b6a1 100644
--- a/drivers/opp/debugfs.c
+++ b/drivers/opp/debugfs.c
@@ -37,10 +37,12 @@ static ssize_t bw_name_read(struct file *fp, char __user *userbuf,
size_t count, loff_t *ppos)
{
struct icc_path *path = fp->private_data;
+ const char *name = icc_get_name(path);
char buf[64];
- int i;
+ int i = 0;

- i = scnprintf(buf, sizeof(buf), "%.62s\n", icc_get_name(path));
+ if (name)
+ i = scnprintf(buf, sizeof(buf), "%.62s\n", name);

return simple_read_from_buffer(userbuf, count, ppos, buf, i);
}
--
2.31.1.272.g89b43f80a514

2024-03-04 11:42:24

by Dhruva Gole

Subject: Re: [PATCH V2 1/2] OPP: debugfs: Fix warning with W=1 builds

Hi,

On 04/03/24 16:52, Viresh Kumar wrote:
> We currently get the following warning:
>
> debugfs.c:105:54: error: '%d' directive output may be truncated writing between 1 and 11 bytes into a region of size 8 [-Werror=format-truncation=]
> snprintf(name, sizeof(name), "supply-%d", i);
> ^~
> debugfs.c:105:46: note: directive argument in the range [-2147483644, 2147483646]
> snprintf(name, sizeof(name), "supply-%d", i);
> ^~~~~~~~~~~
> debugfs.c:105:17: note: 'snprintf' output between 9 and 19 bytes into a destination of size 15
> snprintf(name, sizeof(name), "supply-%d", i);
>
> Fix this and another potential issues it by allocating larger arrays.

Just to keep in mind while applying maybe: s/another/other

> Use the exact string format to allocate the arrays without getting into
> these issues again.
> Reported-by: kernel test robot <[email protected]>
> Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
> Signed-off-by: Viresh Kumar <[email protected]>
> ---
> V2: Use string name while allocating memory for the array to fix potential
> issues later on.
>
> drivers/opp/debugfs.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/opp/debugfs.c b/drivers/opp/debugfs.c
> index ec030b19164a..27c3748347af 100644
> --- a/drivers/opp/debugfs.c
> +++ b/drivers/opp/debugfs.c
> @@ -56,11 +56,11 @@ static void opp_debug_create_bw(struct dev_pm_opp *opp,
> struct dentry *pdentry)
> {
> struct dentry *d;
> - char name[20];
> + char name[] = "icc-path-XXXXXXXXXX"; /* Integers can take 10 chars max */

LGTM!

> int i;
>
> for (i = 0; i < opp_table->path_count; i++) {
> - snprintf(name, sizeof(name), "icc-path-%.1d", i);
> + snprintf(name, sizeof(name), "icc-path-%d", i);
>
> /* Create per-path directory */
> d = debugfs_create_dir(name, pdentry);
> @@ -78,7 +78,7 @@ static void opp_debug_create_clks(struct dev_pm_opp *opp,
> struct opp_table *opp_table,
> struct dentry *pdentry)
> {
> - char name[12];
> + char name[] = "rate_hz_XXXXXXXXXX"; /* Integers can take 10 chars max */
> int i;
>
> if (opp_table->clk_count == 1) {
> @@ -100,7 +100,7 @@ static void opp_debug_create_supplies(struct dev_pm_opp *opp,
> int i;
>
> for (i = 0; i < opp_table->regulator_count; i++) {
> - char name[15];
> + char name[] = "supply-XXXXXXXXXX"; /* Integers can take 10 chars max */

Feels like a better solution to me than the previous revision, thanks!


Reviewed-by: Dhruva Gole <[email protected]>

>
> snprintf(name, sizeof(name), "supply-%d", i);
>

--
Thanks and Regards,
Dhruva Gole

2024-03-04 11:53:34

by Dhruva Gole

Subject: Re: [PATCH 2/2] OPP: debugfs: Fix warning around icc_get_name()

Hi,

On 04/03/24 16:52, Viresh Kumar wrote:
> If the kernel isn't built with interconnect support, icc_get_name()
> returns NULL and we get following warning:
>
> drivers/opp/debugfs.c: In function 'bw_name_read':
> drivers/opp/debugfs.c:43:42: error: '%.62s' directive argument is null [-Werror=format-overflow=]
> i = scnprintf(buf, sizeof(buf), "%.62s\n", icc_get_name(path));
>
> Fix it.
>
> Reported-by: kernel test robot <[email protected]>
> Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
> Signed-off-by: Viresh Kumar <[email protected]>
> ---

Do we not need this:

Fixes: 0430b1d5704b0 ("opp: Expose bandwidth information via debugfs")

?

> drivers/opp/debugfs.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/opp/debugfs.c b/drivers/opp/debugfs.c
> index 27c3748347af..a9ebfdf0b6a1 100644
> --- a/drivers/opp/debugfs.c
> +++ b/drivers/opp/debugfs.c
> @@ -37,10 +37,12 @@ static ssize_t bw_name_read(struct file *fp, char __user *userbuf,
> size_t count, loff_t *ppos)
> {
> struct icc_path *path = fp->private_data;
> + const char *name = icc_get_name(path);
> char buf[64];
> - int i;
> + int i = 0;
>
> - i = scnprintf(buf, sizeof(buf), "%.62s\n", icc_get_name(path));
> + if (name)
> + i = scnprintf(buf, sizeof(buf), "%.62s\n", name);

Reviewed-by: Dhruva Gole <[email protected]>

>
> return simple_read_from_buffer(userbuf, count, ppos, buf, i);
> }

--
Thanks and Regards,
Dhruva Gole

2024-03-05 06:10:04

by Viresh Kumar

Subject: Re: [PATCH V2 1/2] OPP: debugfs: Fix warning with W=1 builds

On 04-03-24, 17:08, Dhruva Gole wrote:
> Hi,
>
> On 04/03/24 16:52, Viresh Kumar wrote:
> > We currently get the following warning:
> >
> > debugfs.c:105:54: error: '%d' directive output may be truncated writing between 1 and 11 bytes into a region of size 8 [-Werror=format-truncation=]
> > snprintf(name, sizeof(name), "supply-%d", i);
> > ^~
> > debugfs.c:105:46: note: directive argument in the range [-2147483644, 2147483646]
> > snprintf(name, sizeof(name), "supply-%d", i);
> > ^~~~~~~~~~~
> > debugfs.c:105:17: note: 'snprintf' output between 9 and 19 bytes into a destination of size 15
> > snprintf(name, sizeof(name), "supply-%d", i);
> >
> > Fix this and another potential issues it by allocating larger arrays.
>
> Just to keep in mind while applying maybe: s/another/other
>
> > Use the exact string format to allocate the arrays without getting into
> > these issues again.
> > Reported-by: kernel test robot <[email protected]>
> > Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
> > Signed-off-by: Viresh Kumar <[email protected]>
> > ---
> > V2: Use string name while allocating memory for the array to fix potential
> > issues later on.
> >
> > drivers/opp/debugfs.c | 8 ++++----
> > 1 file changed, 4 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/opp/debugfs.c b/drivers/opp/debugfs.c
> > index ec030b19164a..27c3748347af 100644
> > --- a/drivers/opp/debugfs.c
> > +++ b/drivers/opp/debugfs.c
> > @@ -56,11 +56,11 @@ static void opp_debug_create_bw(struct dev_pm_opp *opp,
> > struct dentry *pdentry)
> > {
> > struct dentry *d;
> > - char name[20];
> > + char name[] = "icc-path-XXXXXXXXXX"; /* Integers can take 10 chars max */

Integers can take 11 chars max, I forgot the negative symbol. Added
space for another byte and pushed the changes.

> Feels like a better solution to me than the previous revision, thanks!
>
>
> Reviewed-by: Dhruva Gole <[email protected]>

Thanks.

--
viresh